This invention relates to a technique for preventing peeling of a package interface and cracking when a surface package type semiconductor package is mounted to a packaging substrate such as a printed circuit board.
In surface mount package type semiconductor packages such as a small outline package (SOP), a squad flat package (QFP), a plastic leaded chip carrier (PLCC), and the like, the size and thickness of the packages are more and more reduced in order to cope with the increase in the size of a semiconductor chip stored in the package, and package strength tends to decrease.
Therefore, it has become difficult to produce a thin resin molded IC having high reliability.
Incidentally, mentioned can be made of "IC PACKAGING TECHNIQUE", published by Kogyo Chosakai K.K., Jan.15, 1980, pp. 135-156, as a prior art reference describing surface package type semiconductor packages.
Furthermore, as disclosed in Japanese Patent Laid-Open No. 178877/1986 by Otsuka et al. (Aug. 11, 1986), a proposal has been made to put a desiccant into a magazine or to seal a conveying tray in a bag of a vinyl sheet or the like.